Neurophysiological and Ultrasound Correlations in Guillain Barré Syndrome and CIDP-Case Series.

INTRODUCTION: Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are inflammatory polyneuropathies with an autoimmune etiology. These diseases differ mainly in the timing of their course but also in certain clinical differences. Electroneurography and electromyography are crucial for fulfilling the primary (for CIDP) and secondary (for GBS) diagnostic criteria. High-resolution ultrasound (HRUS) is recognized as a complementary method in the diagnosis of CIDP and GBS. AIM: The aim of this study was to present the neurophysiological and ultrasound findings of patients with clinically diagnosed inflammatory neuropathies (GBS and CIDP). MATERIAL AND METHODS: We collected data from clinically confirmed patients with GBS (3 persons) and CIDP (6 persons). The neurography and high-resolution ultrasound examinations according to the UPSS scale were performed. RESULTS: The neurography tests of GBS and CIDP patients showed mainly demyelinating lesions of the examined nerves, often with abnormal F-wave recordings. Examination using HRUS in GBS patients showed mild and regional nerve swelling with hypoechoic bundles with a predilection for proximal segments and cervical spinal nerve roots. In contrast, CIDP patients had diffused nerve swelling with hypoechoic bundles of greater severity and extent than those with GBS. CONCLUSION: Neurophysiological tests and HRUS of peripheral nerves, plexi, and roots performed together can be very valuable, complementary diagnostic methods for the early diagnosis and effective treatment of inflammatory polyneuropathies.

Predictors of Recovery in Facial Nerve Palsy: Insights From an Observational Study in Odisha, India.

Background Facial nerve paralysis, leading to the loss of facial expression, poses significant discomfort to patients. While most individuals exhibit a favorable response to treatment, a subset experiences enduring facial deformities without clearly defined etiology. This study aimed to identify prognostic factors influencing outcomes and quality of life in facial nerve palsy patients, contributing to enhanced clinical management. Methods A prospective observational study was conducted in the Otorhinolaryngology Department of Maharaja Krishna Chandra Gajapati Medical College and Hospital, a tertiary care hospital. We included patients presenting with any clinical variety of facial nerve palsy, irrespective of age and gender. Only moribund and noncompliant cases were excluded. Patients underwent clinical assessment using the House-Brackmann (HB) grading at presentation and were subsequently monitored at three weeks, three months, and six months post-onset to assess recovery. Results Out of 66 patients, 18 (27.27%) fully recovered at three weeks, 50 (75.76%) recovered at three months, and 54 (81.82%) at six-month follow-up. Incomplete recovery was observed in 13 (19.69%) patients. Factors associated with favorable outcomes included younger age of onset (p = 0.003), lower baseline HB grade (IV or less) (p = 0.001), Electroneurography Degeneration Index (ENoG DI) of <70% (p < 0.0001), early initiation of treatment (within five days of onset) (p = 0.0003), and absence of comorbid conditions (p = 0.03). Gender and affected side (left or right) did not influence the outcome. Conclusion In summary, age, associated comorbid conditions, baseline HB grade, and extent of facial nerve degeneration are crucial predictors of outcomes in facial nerve palsy. This knowledge can guide clinicians in optimizing treatment strategies for improved patient care.

Peripheral Neuropathy in Patients with Hepatitis C Infection-Reversibility after HCV Eradication: A Single Center Study.

Chronic hepatitis C virus (HCV) infection is characterized by a variety of extra-hepatic manifestations; peripheral neuropathy (PN) is one of the most common, especially when mixed cryoglobulinemia (MCG) is present. The prevalence and risk factors of HCV-related PN in the absence of MCG are largely unknown. We conducted a prospective, single-center study, examining the prevalence and reversibility of HCV-associated neuropathy in the absence of MCG. Nerve fiber density in the epidermis was evaluated through skin biopsy and electroneurography (ENG) before HCV-treatment initiation and 1 year post sustained virological remission (SVR). Forty HCV-infected individuals (nine HIV co-infected) with no other neuron-harming factors were included; four other HCV mono- and three HIV co-infected individuals were excluded due to presence of diabetes, B12 insufficiency, or neurotoxic drugs. Twelve consecutive controls with no neuron-harming conditions were also recruited; eight more were excluded due to meeting exclusion criteria. Four patients had ENG signs of polyneuropathy (two with HCV mono- and two with HIV co-infection), while seven more (five with HCV mono- and two with HIV co-infection) had signs of mono-neuropathy, leading to PN prevalences of 22.5% and 44% for mono- and co-infection, respectively (p value 0.179). The two patients with HCV mono-infection and polyneuropathy and the one with ulnar nerve damage showed ENG improvement 1 year post SVR. Regarding intraepidermal nerve density, HCV infection, irrespective of HIV co-infection, was correlated with a lower intraepidermal neuron density that improved 1 year post SVR (p value 0.0002 for HCV and 0.0326 for HCV/HIV co-infected patients). PN is common in HCV infection; successful eradication of HCV leads to PN improvement.

Prognostic value of electroneurography using the midline method for predicting the development of synkinesis after peripheral facial palsy.

OBJECTIVE: The prognostic value of electroneurography (ENoG) for predicting the incidence of synkinesis is reportedly about 40 % using the formal standard method (ENoG-SM). However, the prognostic value of ENoG using the newly developed midline method (ENoG-MM) has not been determined. The aim of this study was to demonstrate the optimal prognostic value and advantages of ENoG-MM for predicting the incidence of synkinesis. METHODS: Participants were 573 patients treated for peripheral facial palsy including Bell's palsy or Ramsay Hunt syndrome. We investigated the clinical presence of any oral-ocular or ocular-oral synkinesis from the medical records. ENoG-MM and ENoG-SM were performed 10-14 days after symptom onset. In ENoG-MM, compound muscle action potentials were recorded by placing the anode on the mental protuberance and the cathode on the philtrum. In ENoG-SM, electrodes were placed on the nasolabial fold. Synkinesis was clinically assessed at the end of follow-up or at >1 year after onset. The sensitivity and specificity of ENoG values for predicting the incidence of synkinesis were compared between ENoG-MM and ENoG-SM at every 5 % around 40 % (range, 30-50 %). RESULTS: At every 5 % of ENoG values around 40 %, ENoG-MM provided higher sensitivity and lower specificity for predicting the incidence of synkinesis compared with ENoG-SM. In particular, when the cut-off value was set at 45 %, sensitivity was 100 % and 95.3 % with ENoG-MM and ENoG-SM, respectively. CONCLUSION: In peripheral facial palsy, ENoG-MM offered higher sensitivity than ENoG-SM for predicting synkinesis. ENoG-MM is useful for screening patients at risk of developing synkinesis. In clinical practice, an ENoG-MM cut-off value of 45 % must be the optimal prognostic value because of the 100 % sensitivity.

A Proposal for Neurography Referral in Patients with Carpal Tunnel Syndrome Based on Clinical Symptoms and Demographic Variables of 797 Patients.

The clinical manifestation of median nerve entrapment at the carpal tunnel level is known as carpal tunnel syndrome (CTS). Electroneurography (ENG) is considered the gold standard in CTS evaluation. We conducted a retrospective study and analyzed some clinical and demographic variables, relating them to the degree of neuropathy using ENG, to better understand the role of ENG in this very common disease. We studied 816 patients referred to our service for neurographic evaluation. Their symptoms were classified as compatible with CTS (cCTS) (n = 646) and atypical for CTS (aCTS) (n = 170). A blind ENG was performed on 797 patients. Patient characteristics were coded as variables and analyzed to study whether they could predict neuropathy severity (sensory and motor involvement or grade ≥ 3 in our classification). We found a correlation between typical symptomatology, age over 50 years, male gender, positivity of Phalen's maneuver and Tinel's sign, and a neuropathy grade ≥ 3. We also found a correlation with CTS in the contralateral hand if the other hand showed neuropathy, despite the lack of symptoms in this hand. We propose a practical algorithm for ENG referral based on clinical symptoms, demographic factors, and neurophysiological variables.

Prognostic Value of Electroneuronography in Severe Cases of Facial Palsy.

OBJECTIVE: To examine the prognostic value of electroneuronography (ENoG) in predicting functional recovery in severe cases of acute facial palsy. METHODS: Patients with severe degrees of facial palsy (initial House-Brackmann [HB] grades IV to VI) with available electrodiagnostic studies conducted 2-4 weeks after symptom onset were reviewed retrospectively. The patients were categorized into "good recovery" and "poor recovery" groups, with the former showing mild to no dysfunction (HB I to III) and the latter exhibiting moderate to severe dysfunction (HB IV to VI) on follow-up evaluation, 2 months after onset. ENoG amplitudes in four facial muscles (frontalis, nasalis, orbicularis oculi, and orbicularis oris), as well as age, sex, affected side, disease etiology, comorbidities, and laboratory findings, were compared between the two groups. RESULTS: Thirty-seven patients were included. Twenty-nine of the patients showed "good recovery," and eight showed "poor recovery" at 2 months after symptom onset. Univariate analysis yielded no significant difference in age, sex, affected side, disease etiology, comorbidities, and laboratory findings between the two groups. Preserved ENoG amplitudes (individual, average, and trimmed means) were significantly higher in the good recovery group than in the poor recovery group (p<0.005). Sex (p=0.038) and the ENoG of the nasalis muscle, acquired 2-4 weeks from symptom onset (p=0.004), showed significant differences in multivariate regression analysis. CONCLUSION: This study suggests that the female sex and lower ENoG of the nasalis muscle, acquired 2-4 weeks from symptom onset, have negative prognostic value for the 2-month functional outcome of severe facial palsy cases.

Comparison of Motor Evoked Potentials Neuromonitoring Following Pre- and Postoperative Transcranial Magnetic Stimulation and Intraoperative Electrical Stimulation in Patients Undergoing Surgical Correction of Idiopathic Scoliosis.

The relationships between the results of pre- and intraoperative motor evoked potential recordings during neuromonitoring and whether idiopathic scoliosis (IS) surgical correction improves the spinal efferent transmission have not been specified in detail. This study aims to compare the results of surface-recorded electromyography (EMG), electroneurography (ENG, M, and F-waves), and especially motor evoked potential (MEP) recordings from tibialis anterior muscle (TA) bilaterally in 353 girls with right idiopathic scoliosis (types 1-3 according to Lenke classification). It has not yet been documented whether the results of MEP recordings induced by transcranial single magnetic stimulus (TMS, pre- and postoperatively) and trains of electrical stimuli (TES; intraoperatively in T0-before surgery, T1-after pedicle screws implantation, and T2-after scoliosis curvature distraction and derotation following two-rod implantation) can be compared for diagnostic verification of the improvement of spinal cord neural transmission. We attempted to determine whether the constant level of optimal anesthesia during certain surgical steps of scoliosis treatment affects the parameters of MEPs recorded during neuromonitoring procedures. No neurological deficits have been observed postoperatively. The values of amplitudes but not latencies in MEP recordings evoked with TMS in IS patients compared before and after surgery indicated a slight improvement in efferent neural transmission. The results of all neurophysiological studies in IS patients were significantly asymmetrical and recorded worse on the concave side, suggesting greater neurological motor deficits at p = 0.04. The surgeries brought significant improvement (p = 0.04) in the parameters of amplitudes of sEMG recordings; however, the consequences of abnormalities in the activity of TA motor units were still reflected. ENG study results showed the symptoms of the axonal-type injury in peroneal motor fibers improving only on the concave side at p = 0.04, in parallel with F-wave parameters, which suggests that derotation and distraction might result in restoring the proper relations of the lumbar ventral roots in the spinal central canal, resembling their decompression. There were no significant differences detected in the amplitudes or latencies of MEPs induced with TMS or TES when comparing the parameters recorded preoperatively and intraoperatively in T0. The amplitudes of TES-evoked MEPs increased gradually at p = 0.04 in the subsequent periods (T1 and T2) of observation. A reduction in MEP latency at p = 0.05 was observed only at the end of the IS surgery. Studies on the possible connections between the level of anesthesia fluctuations and the required TMS stimulus strength, as well as the MEP amplitude changes measured in T0-T2, revealed a lack of relationships. These might not be the factors influencing the efferent transmission in spinal pathways beside the surgical procedures. Pre- (TMS-evoked) and intraoperative (TES-evoked) recordings are reliable for evaluating the patient's neurological status before and during surgical scoliosis correction procedures. An increase in MEP amplitude parameters recorded on both sides after scoliosis surgery proves the immediate improvement of the total efferent spinal cord transmission. Considering comparative pre- and postoperative sEMG and ENG recordings, it can be concluded that surgeries might directly result in additional lumbar ventral root decompression. We can conclude that MEP parameter changes are determined by the surgery procedures during neuromonitoring, not the anesthesia conditions if they are kept stable, which influences a decrease in the number of false-positive neuromonitoring warnings.

End-to-Side vs. Free Graft Nerve Reconstruction-Experimental Study on Rats.

The long history of regeneration nerve research indicates many clinical problems with surgical reconstruction to be resolved. One of the promising surgical techniques in specific clinical conditions is end-to-side neurorrhaphy (ETS), described and then repeated with different efficiency in the 1990s of the twentieth century. There are no reliable data on the quality of recipient nerve regeneration, possible donor nerve damage, and epineural window technique necessary to be performed. This research attempts to evaluate the possible regeneration after end-to-side neurorrhaphy, its quality, potential donor nerve damage, and the influence of epineural windows on regeneration efficiency. Forty-five female Wistar rats were divided into three equal groups, and various surgical technics were applied: A-ETS without epineural window, B-ETS with epineural window, and C-free graft reconstruction. The right peroneal nerve was operated on, and the tibial nerve was selected as a donor. After 24 weeks, the regeneration was evaluated by (1) footprint analysis every two weeks with PFI (peroneal nerve function index), TFI (tibial nerve function index), and SFI (sciatic nerve function index) calculations; (2) the amplitude and latency measurements of motor evoked potentials parameters recorded on both sides of the peroneal and tibial nerves when electroneurography with direct sciatic nerve electrical stimulation and indirect magnetic stimulation were applied; (3) histomorphometry with digital conversion of a transverse semithin nerve section, with axon count, fibers diameter, and calculation of axon area with a semiautomated method were performed. There was no statistically significant difference between the groups investigated in all the parameters. The functional indexes stabilized after eight weeks (PFI) and six weeks (TFI and SFI) and were positively time related. The lower amplitude of tibial nerve potential in groups A and B was proven compared to the non-operated side. Neurophysiological parameters of the peroneal nerve did not differ significantly. Histomorphometry revealed significantly lower diameter and area of axons in operated peroneal nerves compared to non-operated nerves. The axon count was at a normal level in every group. Tibial nerve parameters did not differ from non-operated values. Regeneration of the peroneal nerve after ETS was ascertained to be at the same level as in the case of free graft reconstruction. Peroneal nerves after ETS and free graft reconstruction were ascertained to have a lower diameter and area than non-operated ones. The technique of an epineural window does not influence the regeneration result of the peroneal nerve. The tibial nerve motor evoked potentials were characterized by lower amplitudes in ETS groups, which could indicate axonal impairment.

Vagus nerve stimulation using an endovascular electrode array.

Objective. Vagus nerve stimulation (VNS), which involves a surgical procedure to place electrodes directly on the vagus nerve (VN), is approved clinically for the treatment of epilepsy, depression, and to facilitate rehabilitation in stroke. VNS at surgically implanted electrodes is often limited by activation of motor nerve fibers near and within the VN that cause neck muscle contraction. In this study we investigated endovascular VNS that may allow activation of the VN at locations where the motor nerve fibers are not localized.Approach. We used endovascular electrodes within the nearby internal jugular vein (IJV) to electrically stimulate the VN while recording VN compound action potentials (CAPs) and neck muscle motor evoked potentials (MEPs) in an acute intraoperative swine experiment.Main Results. We show that the stimulation electrode position within the IJV is critical for efficient activation of the VN. We also demonstrate use of fluoroscopy (cone beam CT mode) and ultrasound to determine the position of the endovascular stimulation electrode with respect to the VN and IJV. At the most effective endovascular stimulation locations tested, thresholds for VN activation were several times higher than direct stimulation of the nerve using a cuff electrode; however, this work demonstrates the feasibility of VNS with endovascular electrodes and provides tools to optimize endovascular electrode positions for VNS.Significance. This work lays the foundation to develop endovascular VNS strategies to stimulate at VN locations that would be otherwise too invasive and at VN locations where structures such as motor nerve fibers do not exist.

The Usefulness of Motor Potentials Evoked Transvertebrally at Lumbar Levels for the Evaluation of Peroneal Nerve Regeneration after Experimental Repair in Rats.

Motor evoked potentials (MEPs) are used in neurology as part of a precise diagnostic method to study the transmission of efferent neural impulses at the central and peripheral levels of the nervous system. Previous attempts have been made to apply MEPs in animal studies for evaluating neural transmission at the motor cortex center level to the muscles of the forelimbs and hindlimbs. In clinical and experimental studies, little attention is focused on the significance of the magnetic stimulation of spinal cord structures with the direct recording of the evoked potentials from peripheral nerve motor fibers. The aim of this paper was to evaluate the usefulness of the motor potentials evoked transvertebrally at lumbar levels in the evaluation of experimental peroneal nerve regeneration in rats. The bilateral transmission of efferent impulses in the distal parts of the peroneal and tibial nerves was verified by recordings of evoked potentials following transvertebral magnetic stimulation at lumbar levels (MEPs) and the electrical stimulation of the sciatic nerve in classical electroneurographic (ENG) tests for comparison. Recordings were performed 24 weeks after grafts on surgically treated hindlimbs as well as on non-operated hindlimbs as controls. Both the MEP and ENG stimulations resulted in evoked potentials with larger amplitude values following the application of the magnetic pulses, with more being recorded on the non-operated hindlimbs than on the operated ones when recordings were taken from peroneal nerve branches. We observed statistically significant correlations between the MEP and ENG results for peroneal and tibial nerve amplitude on the non-operated side and peroneal nerve amplitude on the operated side. The recorded latencies of the evoked potentials were shorter in the ENG studies than in the MEPs for the non-operated side. The results demonstrated the phenomenon of regeneration in the motor fibers of the peroneal nerves 24 weeks after grafting in the experimental conditions. In this study, the MEPs were as useful as the ENG studies for evaluating regeneration in the motor fibers of hindlimb nerves in rats, although they were not significantly different. This paper discusses the clinical importance of transvertebral MEPs induced at the lumbosacral and cervical levels with a magnetic field for the diagnostic evaluation of efferent impulse transmission at different levels of the motor pathway.

Clinical Onset of Action of Incobotulinum Toxin A Preparation.

BACKGROUND: Many studies in vitro compared the onset of action, maximum efficacy, and duration of botulinum toxin type A (BoNT/A) preparations. OBJECTIVE: In this study, we analyzed the onset of action of BoNT/A preparation free of complexing proteins in patients with upper limb spasticity post stroke up to 30 days after treatment. METHODS: 75 patients affected by Biceps Brachii spasticity were enrolled. Outcome measures were instrumental muscle tone modification (myometric measurement), improvement of Modified Ashworth Scale (MAS), improvement of elbow's passive extension, and improvement of compound muscle action potential (cMAP) evaluated by electroneurography. We analyzed data at t0 (pre-injection), t1 (1 day after), t2 (7 days after), t3 (14 days after), and t4 (30 days after). RESULTS: All measurements decreased at t2, t3, and t4 with initial improvement at t2 and maximum improvement at t4; no statistical difference at t1 was found. CONCLUSION: This study demonstrated the onset of Incobotulinumtoxin A efficacy started after 7 days; this rapid action and efficacy of BoNT/A preparation could improve an intensive rehabilitation program after some days post-injection. Early clinical onset of action could be by the absence of complexing proteins in the preparation.

An electrophysiological prognostic diagnosis for facial palsy.

Two electrophysiological tests for facial palsy-electroneurography (ENoG) and nerve excitability test (NET)-were reviewed. ENoG has advantages over NET in that it reflects the percentage of degenerated facial nerve fibers and can provide an accurate prognosis. However, as disadvantages, ENoG requires large, expensive equipment, and such supramaximal electrical stimulation can be quite painful for patients. NET is less painful due to weak stimulation with just enough current to meet the threshold, and the required equipment is compact and inexpensive to procure. However, it is impossible to calculate the percentage of degenerated nerve fibers, and NET is inferior to ENoG in terms of accurate prognostic prediction for facial palsy. The appropriate timing for both ENoG and NET is 7 to 10 days after the onset. While ENoG has proven more popular than NET because of its accuracy for prognostic prediction, we should not predict the prognosis of facial palsy based solely on the results of electrophyisiolgical examinations; a comprehensive evaluation including the facial muscle grading system is essential.

Electroneurological changes in peripheral nerves in patients post-COVID.

Various neurological manifestations are observed in about 36.4% of patients infected with SARS-CoV-2 and post-COVID neuropathy is one of them. There is lack of studies describing neurophysiological abnormalities in peripheral nerves in case of patients who had SARS-CoV-2 infection. The aim of this study was to analyze the changes in peripheral nervous system in case of COVID-19 survivors. In the presented study, 45 COVID-19 survivors who had nerve conduction study (NCS) were involved. Results were compared with control group consisting of healthy patients who had nerve conduction study before the COVID-19 pandemic. In our study group, neurophysiological abnormalities were present in the case of both sensory and motor nerve fibers. The most significant reduction of NCS parameters was observed in the case of sensory action potential amplitude of sural nerve. Moreover, that correlation was the most significant in the case of amplitude and conduction velocity in sensory and motor neuron fibers both in arms and legs. Those abnormalities were observed even 6 mo after COVID-19. Further investigation needs to be done regarding the polyneuropathies associated with human coronaviruses, and we should answer the question whether the virus directly damages peripheral nerves or factors mediating inflammatory response are responsible for the neural damage.NEW & NOTEWORTHY Various neurological manifestations are observed in about 36.4% of patients infected with SARS-CoV-2 and post-COVID neuropathy is one of them. There is lack of studies describing neurophysiological abnormalities in peripheral nerves in case of patients who had SARS-CoV-2 infection. The aim of this study was to analyze changes in peripheral nervous system in case of COVID-19 survivors.

Electroneurography Values Based on Degree of Facial Muscle Contraction Response to Electroacupuncture in Patients with Peripheral Facial Nerve Palsy: A Retrospective Study.

Objective: Japanese acupuncture practice cannot easily predict the prognosis of patients with peripheral facial palsy. Electroneurography (ENoG) predicts prognosis in patients with peripheral facial palsy; however, the difference between ENoG values and degree of facial muscle contraction response (FMCR) to electroacupuncture stimulation (ES) targeting the affected facial nerve is unexplored. Therefore, an exploratory evaluation of the differences in ENoG values was conducted across the degrees of FMCR induced by ES targeting the affected facial nerve in patients with peripheral facial nerve palsy. Methods: In total, 90 patients with peripheral facial nerve palsy were selected who underwent acupuncture treatment at the Department of Oriental Medicine, Saitama Medical University Hospital, between January 2005 and December 2014. The FMCR degree and ENoG values were assessed through patients' medical records. The patients were divided into excellent, moderate, and noresponse groups (65, 16, and 9 patients, respectively) according to the FMCR degree. The differences in ENoG values were analyzed among the groups. Results: The ENoG values were 26.6% (10.4%-55.9%), 2.45% (0.35%-8.80%), and 2.00% (0.00%-5.10%) for the excellent, moderate, and no-response groups, respectively. These values significantly differed between the excellent group and the no-response (P < 0.01) and moderate (P < 0.01) groups. Conclusion: The ENoG values varied according to degree of FMCR induced by ES targeting the facial nerve in patients with peripheral facial nerve palsy. This might allow to predict the prognosis based on the ES-induced FMCR.

Prospective Assessment of Risk Factors Influencing Facial Nerve Paresis in Patients after Surgery for Parotid Gland Tumors.

Background and objectives: Facial weakness is the most important complication of parotid gland tumor surgery. The aims of this study are as follows: (1) assessment of the prevalence of postparotidectomy facial nerve dysfunction; (2) clinical and electrophysiological assessment of the facial nerve function before parotidectomy and at 1 and 6 months postoperatively; (3) assessment of the association of postoperative facial palsy with selected risk factors; and (4) assessment of the correlation between the results of clinical and neurophysiological assessments of facial nerve function. Materials and Methods: This study comprised 50 patients (aged 24-75 years) who underwent parotidectomy at the Department of Otolaryngology and Laryngological Oncology in Zabrze, Poland between 2015 and 2017. The evaluation included neurological, clinical and electrophysiological assessments of the facial nerve prior to surgery and at 1 and 6 months postoperatively. Results: No facial palsy was found preoperatively or 6 months postoperatively. Facial nerve dysfunction was found in 74% of patients 1 month postoperatively. In most cases (54%), paresis was mild or moderate (House-Brackmann grades II and III). The results of electrophysiological tests before parotidectomy were either normal or showed some mild abnormalities. We found a statistically significant correlation between the clinical assessment of the facial nerve function (based on the House-Brackmann scale) one month postoperatively and the latency of the CMAP response from the orbicularis oculi and orbicularis oris muscles. In all three studies, a statistically significant correlation was found between the amplitude of the compound muscle action potential (CMAP) of the orbicularis oris muscle and the degree of facial nerve weakness. Conclusions: The factors that may influence the risk of postoperative facial nerve paralysis (prolonged surgical time and the size and location of the tumor other than in the superficial lobe only) may indirectly suggest that surgery-related difficulties and/or surgeon experience could be crucial to surgery safety.

A method to establish functional vagus nerve topography from electro-neurographic spontaneous activity.

Bioelectronic medicine is an emerging approach to treat many types of diseases via electrical stimulation of the autonomic nervous system (ANS). Because the vagus nerve (VN) is one of the most important nerves controlling several ANS functions, stimulation protocols based on knowledge of the functional organization of the VN are particularly interesting. Here, we proposed a method to localize different physiological VN functions by exploiting electro-neurographic signals recorded during spontaneous VN fibers activity. We tested our method on a realistic human cervical VN model geometry implanted via epineural or intraneural electrodes. We considered in silico ground truth scenarios of functional topography generated via different functional neural fibers activities covered by background noise. Our method accurately estimated the underlying functional VN topography by outperforming state-of-the-art methods. Our work paves the way for development of spatially selective stimulation protocols targeting multiple VN bodily functions.

Presence of Varicella Zoster Virus DNA in Saliva May Be Associated with the Severity of Ramsay Hunt Syndrome.

Background: The relationship between varicella zoster virus (VZV) collected from saliva and Ramsay Hunt syndrome (RHS) remains unclear. Therefore, this study aimed to investigate whether VZV DNA in saliva alters the clinical symptoms and prognosis of RHS. Methods: To measure the severity of clinical symptoms of 100 RHS patients, the initial House−Brackmann (HB) grade and associated symptoms were evaluated. The final HB grade at the end of treatment was measured to determine the prognosis. Electroneurography (ENoG) was performed on four facial muscles, including the frontalis, oculi, nasalis, and oris. Results: Salivary VZV DNA was isolated from 72 patients with RHS. The VZV DNA-positive group was 34.023 times more likely to have severe initial HB grade than the control group (95% CI, 3.21−359.68; p = 0.003). There were no significant differences in final HB grade. All ENoG values of the VZV DNA-positive group were significantly higher than those of the control group (frontalis, p = 0.003; oculi, p = 0.001; nasalis, p < 0.001; oris, p = 0.037). Conclusions: RHS patients with salivary VZV DNA have more severe clinical symptoms than the control group. There were no differences in prognosis and associated symptoms. A VZV DNA test using saliva samples of patients with RHS can evaluate the clinical symptoms and provide early confirmation of VZV infection, enabling timely treatment in a non-invasive way.

Phenotypic Characterization of Laryngospasm: The Utility of Laryngeal Neurophysiological Studies.

OBJECTIVE: To determine the existence of laryngeal neuropathy and the influence of gastroesophageal reflux in patients with episodic laryngospasm. STUDY DESIGN: Single -center, observational study with prospective clinical collection. STUDY SETTING: Prospective analysis of 18 Spanish patients with episodic laryngospasm in a Spanish Public Center collected by otolaryngologist. The recruitment dates were from January 2019 to December 2019. METHODS: Data collection of 18 patients with episodic laryngospasm. Clinical characteristics, laryngeal neurophysiological studies and reflux esophageal testing were analyzed. RESULTS: All patients have a trigger for the laryngospasms, being the most prevalent adopting the supine position (27.7%). EMG and ENG were pathological in 83.3 and 63.6 % respectively. Chronic bilateral denervation (increased amplitude and duration of potentials) with signs of reinnervation in the non-active chronic phase (large polyphasia), was the most prevalent finding. Evidence of gastroesophageal reflux either by pH meter, Gastroscopy or both was found in 38.8 % of patients. CONCLUSIONS: Neurophysiological studies have confirmed the existence of laryngeal neuropathy in the majority of patients with laryngospasm. A substantial percentage of patients (38.8%) with laryngospasm had objective GERD and improved with PPIs. Laryngeal EMG and ENG can establish a more accurate diagnostic for episodic laryngospams and may supports treatment with neuromodulators.

THE ROLE OF COMORBIDITY IN THE CLINICAL COURSE AND QUALITY OF LIFE OF PATIENTS WITH DIABETIC POLYNEUROPATHY.

OBJECTIVE: The aim: To identify and substantiate the role of comorbidity in the clinical course and quality of life (QOL) of patients with diabetic polyneuropathy (DP). PATIENTS AND METHODS: Materials and methods: We examined 139 patients aged from 19 to 69 years with DP occured as a consequence from type I and II diabetes mellitus (DM). The examined persons were divided into two groups: DP due to type I and II DM with comorbidity (group A,n=93) and without comorbidity (group B,n=46). For the patients was done a comprehensive clinical and neurological examination, laboratory, instrumental methods of examination. RESULTS: Results: We observe hypo- or areflexia much more in group A respect to reflexes on the upper and lower extremities than in group B, where the changes are more noticeable on the lower extremities. The level of QOL in group A is significantly lower than in group B. According to the McGill scale in group A, all indicators of pain characteristics are higher. Quite a high score in group A on the Pain Rating Index(PRI) - 32.17±1.57points. The lowest rates of the nerve conduction velocity (NCV) on the motor fibers were registered in group A, on the sensitive fibers of the upper extremities has got lower rates in groups A and B than in the control group, but in group A it is slightly higher. CONCLUSION: Conclusions: Clinical manifestations of DP in group A are more pronounced than in the comparison group and a wide range of comorbidity was diagnosed, including cardiovascular, which aggravates the manifestations of DP.

Patient-Assessed Outcomes following Temporal Bone Fractures.

The long-term impact of neurotological symptoms after a temporal bone fracture (TBF), including facial nerve palsy (FP), hearing loss, tinnitus, and dizziness on the quality of life of patients is often underevaluated. Thus, we retrospectively assessed 30 patients with TBF (26 men and 4 women) in our university tertiary referral center. They participated from injury onset to the final follow-up, over an 18-month period. Quality of life was estimated using validated questionnaires, such as the Facial Disability Index (FDI: physical and social), Hearing Handicap Inventory (HHI), Tinnitus Handicap Inventory (THI), and Dizziness Handicap Inventory (DHI). The FDI score was significantly worse in patients with severe initial (for physical FDI) and final facial palsy (for both physical and social FDI), mainly with immediate onset. The HHI score was statistically worse in patients with mixed hearing loss compared to those with conductive or sensorineural hearing loss and in those with profound hearing loss vs. normal hearing. The mixed TBF and the severity of hearing loss (especially profound hearing loss) were correlated with HHI, THI and DHI score values. In the long-term period after a TBF, moderate or severe facial palsy, mainly with immediate onset, may cause psychological distress, more easily resulting in social disability than functional impairment. Mixed TBF and mixed or profound hearing loss may also negatively influence quality of life.